Kivy FloatLayout issue: Label not centered per default

Question

I am currently facing a weird situation as my code used to work but does not work in a different context. I basically have a BoxLayout (MainWindow) which contains a first item (BoxLayout), with a canva drawing an Ellipse. The Ellipse is perfectly centered in the BoxLayout. I also have a second BoxLayout which contains some kind of bottom bar. Nonetheless, when I add a FloatLayout to the first BlockLayout containing my Ellipse, the Label ("Hello") inside it is not centered at all inside the parent BoxLayout nor in the Ellipse.

The end result:

End result with Hello not fitting

from kivymd.app import App
from kivy.core.window import Window
from kivy.uix.boxlayout import BoxLayout

Window.size =(290, 590)

class MainWindow(BoxLayout): 
    pass

class TestApp(App):
    def build(self):
        return MainWindow()

TestApp().run()

An my kv file:

<MainWindow>:    
    orientation: "vertical"
    background_color: 0,0,0,1
    BoxLayout:
        id: box
        background_color: 0,0,0,1
        canvas:
            Color:
                rgba: 0,0,255,1
            Ellipse:
                size: 180, 180
                pos: [self.center_x - 180/2, self.center_y - 180/2]
        FloatLayout:
            Label:
                text: "Hello"
    BoxLayout:
        id: BottomBar
        orientation: "horizontal"
        size_hint: 1, .2
        ToggleButton:
            background_color: (0,0,0,1) if self.state == "normal" else (255,0,0,1)
            text: "Stats"
            group: "Bottom"
            state: "down"
            on_press:
                print(root.ids.box.pos)
        ToggleButton:
            text: "Press"
            background_color: (0,0,0,1) if self.state == "normal" else (255,0,0,1)
            group: "Bottom"

I have try to change pos, pos_hint and size of every single element without much success. It feels like the FloatLayout element is not even part of its parent BoxLayout. I also tried GridLayout instead of BoxLayout which does not make it better.

Answer 1

Use RelativeLayout instead of FloatLayout:

RelativeLayout:
    Label:
        text: "Hello"